Infection risks associated with oral sex

Oral sex is now widely practised, in both heterosexual and homosexual relationships.

For many years, it was regarded as an almost 'unmentionable' activity. But these days, research suggests that most sexually active people go in for it sometimes.

In 2013 the National Sexual Attitudes and Lifestyle (NATSAL) survey announced that in all age groups (except the over-65s), the majority of people now say that they have oral sex sometimes.

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For instance, 71 per cent of young adults (age 16 to 24) reported that they'd had oral sex in the last year. And 80 per cent of 25 to 34 year olds said the same thing.

So fellatio and cunnilingus are extremely popular, and are widely regarded as a normal, enjoyable part of a sexual relationship. Furthermore, it's been shown that oral sex has certain positive aspects.

It can be extraordinarily effective at helping women to reach a climax.

It cannot get you pregnant (except under the most extraordinary and unlikely circumstances).

However, a lot of people do – quite understandably – get concerned about whether oral love play could give them any infection.

And around 2010, serious worries began to emerge about whether oral sex can give people human papilloma virus (HPV) in the throat area and whether this could lead to cancer. By 2013, it was clear that these fears were justified.

Also experts have recently pointed out that there appears to be some significant risk of acquiring chlamydia and gonorrhoea through oral sexual activity.

In this article, we look at the various risks.

What is oral sex?

First, let's just clarify what we mean by 'oral sex'. There are several main types.

Cunnilingus (sometimes referred to as 'cunnilinctus') is oral stimulation of a woman's vagina and/or vulva – and especially her clitoris – by her partner's lips and tongue.

Fellatio is stimulation of a man's penis by his partners mouth – usually by licking or sucking. It is often wrongly referred to as 'a blow job' in fact, it is highly dangerous to 'blow' during this manoeuvre (or during cunnilingus).

'Nippling' is sucking or licking your partner's nipples. It carries almost no risk of any infection – except, very rarely, syphilis

Oro-anal sex – often referred to as 'rimming' – is stimulation of the partner's anus with tongue or lips. Clinical experience suggests that it is relatively uncommon in heterosexuals. As the anus isn't a very clean area of the body, there is no doubt that rimming will lead to a transfer of germs to the mouth.

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HIV infection risk

Because of concerns about the possibility of HIV transmission through the widespread practice of oral sex, the UK Department of Health set up an expert group to report back on the matter. In broad summary, their main conclusions were:

HIV can be transmitted by oral sex, though this does not occur frequently

during fellatio, if the man avoids ejaculation, it probably reduces the risk somewhat

in the case of cunnilingus, there may be an increased risk of transmission if the woman is menstruating

there's no evidence that mouthwashes could reduce the risk of infection

using condoms or 'dental dams' during oral sex could reduce the chance of infection, but not eliminate it.

You can see from the above that there is always some risk of transmission of HIV during oral sex, whatever precautions you take. However, you obviously cannot get infected if your partner does not have the virus.

What other germs could you pick up during oral sex?

As any doctor at a genitourinary medicine (GUM) clinic can tell you, it is possible to acquire several forms of sexually transmitted diseases (STD) through oral sex – if the other person if infected.

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Gonorrhoea

Gonorrhoea, a common STD, can be transmitted to the throat during oral sex, especially fellatio. Because of this fact, GUM clinics often take 'throat swabs' these days. In the throat, the germ can cause inflammation, formation of pus and sometimes soreness.

But often, it causes no symptoms at all, and the person just 'carries' it.

In 2011, it was estimated that 1.9 per cent of London prostitutes had unsuspected gonorrhoea in their throats. It's likely that they would give the germ to men whom they fellated.

Syphilis

The lesions ofsyphilisusually appear on the genitals or the anus – and very rarely on the nipple. But they do sometimes appear on the lips or tongue, as a result of oral sex. And the disease can be caught from an infected person's mouth.

However, please bear in mind that in much of Western Europe, syphilis has been quite uncommon for many years. But in England in 2014, there was an alarming 33 per cent rise in the number of infections! There were 4,317 cases in all, the vast majority of them being in males. In fact, there were only about 250 cases among women. A striking fact is that 86 per cent of men with syphilis in 2014 were men who have sex with men.

Chlamydia

Chlamydia trachomatis is a little genital bug that has become almost epidemic among sexually active young people during the early years of the 21st century.

It's estimated that in some parts of the UK at least 10 per cent of younger adults have it.

It is sometimes found in swabs taken from the throat, and it is thought that it can be transmitted by oral sex, particularly fellatio. In 2011, researchers from University College London revealed that 4 per cent of London sex workers had chlamydia in their throats. This finding is of considerable importance, especially as many men go to prostitutes specifically because they want to be fellated.

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Also doctors at Guy's and St Thomas' Hospitals found that about 1 per cent of their gay male patients were carrying chlamydia in the throat.

Please note that if chlamydia gets established in the throat, mouth or nose, it could cause various infections, particularly of the eye. In 2010, doctors warned that oral sex could cause a one-sided chlamydial conjunctivitis, which does not clear up on routine treatment with eye drops.

Infections transferred by oro-anal sex

As we've indicated above, contact between the mouth and the anus will probably result in the transfer of 'bottom germs' – though these will not necessarily cause disease.

But it's now clear that the dangerous bowel organisms Salmonella, Shigella and Campylobacter can all be transmitted by oro-anal contact.

Shigella causes severe stomach cramps, diarrhoea and fever. Because it is now quite common, the Terrence Higgins Trust (0808 802 1221) has issued a useful leaflet on how to avoid it.

Hepatitis A

The word 'hepatitis' means 'inflammation of the liver'.

Hepatitis A is a common viral infection that can cause jaundice and abdominal pain. It is not usually life-threatening, although sufferers can feel very ill.

The virus is often found in faeces in high concentrations and will almost inevitably be present on the apparently clean anal skin of infected individuals. It can be transmitted by oro-anal contact.

Several epidemic outbreaks have been reported among gay men, but heterosexual couples practising oro-anal contact are just as likely to be at risk.

Hepatitis B

Hepatitis B is also a viral infection. It is common in hot countries and around the Mediterranean. It used to be rare in the UK, but rates are rising.

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It is particularly common among people who have had a previous sexually transmitted disease, and among drug users.

It can cause a very serious, potentially fatal, liver disease and chronic liver damage.

It is most commonly transmitted by inoculation of infected blood, by sharing needles for injection, needlestick injuries and the medical use of infected blood products.

Virus particles are found in semen, stool and saliva, as well as blood. There is clear evidence that it can be transmitted through vaginal and anal intercourse, but it is unproven whether it can be transmitted through oral sex. Certainly, there is a theoretical risk.

Hepatitis C

Hepatitis C is another viral infection transmitted in a similar way to hepatitis B and often affects drug users.

Some people with hepatitis C infection were infected with blood products, such as transfusions, prior to adequate screening procedures in the 1980s.

In 2013, it was reported in a US study that the risk of catching hepatitis C through any kind of sex (including oral sex) was low. But it may be greater if you are HIV-positive.

Worms

Threadworms, and probably other worms, can be transmitted by oro-anal contact.

What about herpes?

Herpes simplex virus (HSV) infection is the commonest cause of genital ulceration. There are two types of the virus. Type 1 affects mainly the lip – causing cold sores. Type 2 causes blisters on the genitals.

In the past, it was thought that genital herpes was caused almost exclusively by Type 2, but in recent years it has become clear that many herpes ulcers on the penis or vulva/vagina are actually caused by the Type 1 virus.

Genital herpes is characterised by recurrent bouts of vesicles (small blisters), either on the penis or vulva, or other parts of the female genital tract. These rapidly break down to form small, painful ulcers.

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HSV can also cause pharyngitis, an inflammation of the throat with ulcer formation.

HSV is highly infectious and usually sexually transmitted. There are several reports of transmission through oral sex.

If you have a cold sore on your lip, do not give anyone oral sex – or even kiss them.

What about HPV and the risk of cancer?

In 2010, I was alarmed when an ENT surgeon showed me the larynx (voicebox) of a man who had had a lot of oral sex partners. The patient was hoarse, and he found it difficult to speak. The area round his vocal cords was virtually 'swamped' by a network of fine, white threads. These, it transpired, were caused by the HPV virus. Fortunately, he did recover.

But since then, it has become increasingly clear that today's high rates of oral sex are linked to the rising incidence of throat and mouth cancer,

HPV is carried by many people. There are about 170 different strains of it. Some of them can cause warts, including genital warts. Others can cause cancer – notably cervical cancer and also anal cancer.

According to the American Association for Cancer Research, more than 50 per cent of all oral cancers are now HPV-related – though many others are caused by tobacco or alcohol.

In the light of current evidence, it's clear that both men and women should now be trying to follow a policy of 'risk reduction' where oral sex is concerned.

Risk reduction

Avoiding oral sex altogether is the only way of preventing infection by the oral route, but because it's an important and enjoyable part of most couples' sexual repertoire, this advice is rather impractical.

Limiting the number of your sexual partners and not being pressured into 'casual' oral sex with an unfamiliar partner is an important factor in reducing infection risk.

Consider whether your partner may have, or have had, other sexual partners, and what their infection status might be, before putting yourself at any risk by giving them oral sex – or receiving it.

It's possible to enjoy oral sex using some form of protective barrier. For fellatio, there is a wide variety of flavoured and scented condoms available, ranging from strawberry to curry and from whisky to lager and lime. For cunnilingus,, a dental dam – a thin plastic film – can be used.

Having the anti-HPV vaccine should reduce your risk of catching HPV through oral sex.

If you are concerned that you have, or might be at risk of having any sexually transmitted disease, it's important to seek medical advice as soon as possible.

Finally, you feel you've taken a risk with oral sex, go to your local genitourinary medicine (GUM) clinic. They'll gladly give you a check-up, plus a throat swab if necessary.

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